How is it that a proven and repeated 12.7 @ 105 mph 3700lb Camaro only musters 288hp and 285 lbs/ft on a chassis dyno?
All things considered, like air density and such, doesn't seem to correlate between the two.
My combo is in my sig.

 

More than likely, your converter showing lower than what it should.

Don't worry about low dyno numbers, real numbers are what you get from the track.

 

I thought it might be convertor related. At the last dyno session, the lockup wasn't working.

 

I figured it was convertor related as well. Last dyno session, the lockup wasn't working at all. Next trip, I'll have it rigged so I can force the lockup in drive rather than overdrive only as I test in drive. It'll be interesting to see what the results will be.

 

 

Agreed. A dyno is nothing more than a tuning tool. A very valuable tuning tool but should not be used for bragging rights. ET slips will conduct that job. Dyno numbers are subject to "manipulation" based on many correction factors. I would rather have a great ET and percieved low dyno numbers than the other way around.

 

I have to say I agree. However, it would be nice to get some hardcore data regarding how well I've done in this build. As with the chassis dyno, calculating horsepower from trap speed and et is also subject to some manipulation. Track conditions, air altitude density, etc. I suppose the only real measure of how well an engine as been assembled, would be the engine dyno.Then again, the testing facility offers some pretty pristine conditions. Not to mention that the exhaust system on the engine dyno is very rarely like the exhaust system on the vehicle.
And before anyone says, they don't race dynos....yes they do. The Engine Masters Challenge is one example I can think of. Chassis dyno shoot outs at the various car show venues are another.

 

[QUOTE=skinny z;4600817]I have to say I agree. However, it would be nice to get some hardcore data regarding how well I've done in this build. As with the chassis dyno, calculating horsepower from trap speed and et is also subject to some manipulation. [\QUOTE]

Your HP numbers will be more accurate if you work backwards. Physics doesn't change and you will be at least able to determine your power level for each particular run made. You can then compare it to your dyno numbers and get the overall picture of your set-up. Often times you find your dyno numbers are within 10% your calculated numbers.

 

What brand of dyno? Also the unlocked TCI Street Fighter 10" convertor.

 

Paperwork says Dynojet Research. I figure the unlocked convertor might eat up as much as 20%. Maybe more if I use trap speed to claculate rear wheel horsepower and compare it to the dyno results. Something like 340-350rwhp from the on-line calculators vs 288rwhp from the dyno. Realistically I can't see my engine producing 400chp. I don't the combination is capable but I could be pleasently surprised.
There is one thing I'll say. I don't say much about the dyno numbers as they are embarrasingly low however I'm personally impressed with my track time. Not as impressive as some I read about here but satisfying none the less.